1. Field
The present invention relates to a metal capacitor and a manufacturing method thereof, and more particularly, to a metal capacitor in which an electric conductivity is significantly improved by applying a metal material for an electrolyte and a manufacturing method thereof.
2. Background
An aluminum electrolytic capacitor is used to smooth a power output from a power circuit to be a predetermined value, or is used as a low frequency bypass. Hereinafter, a method of manufacturing the aluminum electrolytic capacitor will be briefly described.
An etching process of etching the surface of an aluminum foil is performed to enlarge a surface area of the aluminum foil and thereby increase an electric capacity. When the etching process is completed, a forming process of forming a dielectric substance on the aluminum foil is performed. When cathode and anode aluminum foils are manufactured through the etching process and the forming process, a slitting process of cutting the manufactured aluminum foil and a separator by as long as a desired width based on the length of a product is performed. When the slitting process is completed, a stitching process of stitching an aluminum lead patch, which is a lead terminal, to the aluminum foil is performed.
When the slitting of the aluminum foil and the separator is completed, a winding process of disposing the separator between the anode aluminum foil and the cathode aluminum foil, and then winding the separator and the aluminum foils in a cylindrical shape and attaching a tape thereto, so as to not be unwounded. When the winding process is completed, an impregnation process of inserting the wound device into an aluminum case and injecting an electrolyte is performed. When the injecting of the electrolyte is completed, a curing process of sealing the aluminum case using a sealing material is performed. When the curling process is completed, an aging process of restoring a damage to the dielectric substance is performed. Through this, the assembly of the aluminum electrolytic capacitor is completed.
Due to advancement in digitalization and slimness of current electronic devices, there is a need for a capacitor having a low impedance in a high frequency. In order to improve the conventional aluminum electrolytic capacitor manufactured as above, a functional layer-type aluminum solid capacitor or a functional tantalum capacitor is used. However, there are problems as follow.
Since the conventional functional layer-type aluminum solid capacitor or the functional tantalum capacitor uses conductive polymer compounds such as polpyrrole or polythiophene, for electrolyte, there are some constraints on the thermal resistance and the withstanding voltage. Also, since a negative electrode is formed by spraying paste such as graphite in turn, the capacitor becomes thicker. Accordingly, there is some constraint on the number of layers and a contact resistance occurs between layers to thereby deteriorate the impedance.